modules/genunix/streams.c

	streams.c revision 595aa6e48d8a5812a3a42afa5f63ee6f772c7f4e
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <mdb/mdb_modapi.h>
#include <mdb/mdb_ks.h>

#include <sys/types.h>
#include <sys/strsubr.h>
#include <sys/stream.h>
#include <sys/modctl.h>
#include <sys/strft.h>
#include <sys/strsun.h>
#include <sys/sysmacros.h>

#include "streams.h"

typedef struct str_flags {
    uint_t strf_flag;
    const char *strf_name;
    const char *strf_descr;
} strflags_t;

typedef struct str_types {
    const char *strt_name;
    int strt_value;
    const char *strt_descr;
} strtypes_t;

typedef struct ftblk_data {
    ftblk_t ft_data;    /* Copy of ftblk */
    int     ft_ix;      /* Index in event list */
    boolean_t ft_in_evlist; /* Iterating through evlist */
} ftblkdata_t;

typedef void qprint_func(queue_t *, queue_t *);
typedef void sdprint_func(stdata_t *, stdata_t *);

#define SF(flag)    flag, #flag

/*
 * Queue flags
 */
static const strflags_t qf[] = {
    { SF(QENAB),        "Queue is already enabled to run"   },
    { SF(QWANTR),       "Someone wants to read Q"       },
    { SF(QWANTW),       "Someone wants to write Q"      },
    { SF(QFULL),        "Q is considered full"          },
    { SF(QREADR),       "This is the reader (first) Q"      },
    { SF(QUSE),     "This queue in use (allocation)"    },
    { SF(QNOENB),       "Don't enable Q via putq"       },
    { SF(QWANTRMQSYNC), "Want to remove sync stream Q"      },
    { SF(QBACK),        "queue has been back-enabled"       },
    { SF(0x00000200),   "unused (was QHLIST)"           },
    { SF(0x00000400),   "unused (was QUNSAFE)"          },
    { SF(QPAIR),        "per queue-pair syncq"          },
    { SF(QPERQ),        "per queue-instance syncq"      },
    { SF(QPERMOD),      "per module syncq"          },
    { SF(QMTSAFE),      "stream module is MT-safe"      },
    { SF(QMTOUTPERIM),  "Has outer perimeter"           },
    { SF(QINSERVICE),   "service routine executing"     },
    { SF(QWCLOSE),      "will not be enabled"           },
    { SF(QEND),     "last queue in stream"          },
    { SF(QWANTWSYNC),   "Streamhead wants to write Q"       },
    { SF(QSYNCSTR),     "Q supports Synchronous STREAMS"    },
    { SF(QISDRV),       "the Queue is attached to a driver" },
    { SF(0x00400000),   "unused (was QHOT)"         },
    { SF(0x00800000),   "unused (was QNEXTHOT)"         },
    { SF(0x01000000),   "unused (was _QNEXTLESS)"       },
    { SF(0x02000000),   "unused"                },
    { SF(_QINSERTING),  "module is inserted with _I_INSERT" },
    { SF(_QREMOVING)    "module is removed with _I_REMOVE"  },
    { SF(_QASSOCIATED), "queue is associated with a device" },
    { 0, NULL,      NULL                    }
};

/*
 * Syncq flags
 */
static const struct str_flags sqf[] = {
    { SF(SQ_EXCL),      "Exclusive access to inner perimeter"   },
    { SF(SQ_BLOCKED),   "qprocsoff in progress"         },
    { SF(SQ_FROZEN),    "freezestr in progress"         },
    { SF(SQ_WRITER),    "qwriter(OUTER) pending or running" },
    { SF(SQ_MESSAGES),  "There are messages on syncq"       },
    { SF(SQ_WANTWAKEUP) "Thread waiting on sq_wait"     },
    { SF(SQ_WANTEXWAKEUP),  "Thread waiting on sq_exwait"       },
    { SF(SQ_EVENTS),    "There are events on syncq"     },
    { 0, NULL,      NULL                    }
};

/*
 * Syncq types
 */
static const struct str_flags sqt[] = {
    { SF(SQ_CIPUT),     "Concurrent inner put procedure"    },
    { SF(SQ_CISVC),     "Concurrent inner svc procedure"    },
    { SF(SQ_CIOC),      "Concurrent inner open/close"       },
    { SF(SQ_CICB),      "Concurrent inner callback"     },
    { SF(SQ_COPUT),     "Concurrent outer put procedure"    },
    { SF(SQ_COSVC),     "Concurrent outer svc procedure"    },
    { SF(SQ_COOC),      "Concurrent outer open/close"       },
    { SF(SQ_COCB),      "Concurrent outer callback"     },
    { 0, NULL,      NULL                    }
};

/*
 * Stdata flags
 */
static const struct str_flags stdf[] = {
    { SF(IOCWAIT),      "someone is doing an ioctl"     },
    { SF(RSLEEP),       "someone wants to read/recv msg"    },
    { SF(WSLEEP),       "someone wants to write"        },
    { SF(STRPRI),       "an M_PCPROTO is at stream head"    },
    { SF(STRHUP),       "device has vanished"           },
    { SF(STWOPEN),      "waiting for 1st open"          },
    { SF(STPLEX),       "stream is being multiplexed"       },
    { SF(STRISTTY),     "stream is a terminal"          },
    { SF(STRGETINPROG), "(k)strgetmsg is running"       },
    { SF(IOCWAITNE),    "STR_NOERROR ioctl running"     },
    { SF(STRDERR),      "fatal read error from M_ERROR"     },
    { SF(STWRERR),      "fatal write error from M_ERROR"    },
    { SF(STRDERRNONPERSIST), "nonpersistent read errors"        },
    { SF(STWRERRNONPERSIST), "nonpersistent write errors"       },
    { SF(STRCLOSE),     "wait for a close to complete"      },
    { SF(SNDMREAD),     "used for read notification"        },
    { SF(OLDNDELAY),    "use old NDELAY TTY semantics"      },
    { SF(0x00020000),   "unused"                },
    { SF(0x00040000),   "unused"                },
    { SF(STRTOSTOP),    "block background writes"       },
    { SF(0x00100000),   "unused"                },
    { SF(0x00200000),   "unused"                },
    { SF(STRMOUNT),     "stream is mounted"         },
    { SF(STRNOTATMARK), "Not at mark (when empty read q)"   },
    { SF(STRDELIM),     "generate delimited messages"       },
    { SF(STRATMARK),    "at mark (due to MSGMARKNEXT)"      },
    { SF(STZCNOTIFY),   "wait for zerocopy mblk to be acked"    },
    { SF(STRPLUMB),     "stream plumbing changes in progress"   },
    { SF(STREOF),       "End-of-file indication"        },
    { SF(STREOPENFAIL), "re-open has failed"            },
    { SF(STRMATE),      "this stream is a mate"         },
    { SF(STRHASLINKS),  "there are I_LINKs under this stream"   },
    { 0, NULL,      NULL                    }
};

static const struct str_flags mbf[] = {
    { SF(MSGMARK),      "last byte of message is marked"    },
    { SF(MSGNOLOOP),    "don't loop message to write side"  },
    { SF(MSGDELIM),     "message is delimited"          },
    { SF(0x08),     "unused"                },
    { SF(MSGMARKNEXT),  "Private: b_next's first byte marked"   },
    { SF(MSGNOTMARKNEXT),   "Private: ... not marked"       },
    { SF(MSGHASREF),    "Private: msg has reference to owner"   },
    { 0, NULL,      NULL                    }
};

#define M_DATA_T 0xff

static const strtypes_t mbt[] = {
    { "M_DATA", M_DATA_T,   "regular data"          },
    { "M_PROTO",    M_PROTO,    "protocol control"      },
    { "M_MULTIDATA", M_MULTIDATA,   "multidata"         },
    { "M_BREAK",    M_BREAK,    "line break"            },
    { "M_PASSFP",   M_PASSFP,   "pass file pointer"     },
    { "M_EVENT",    M_EVENT,    "Obsoleted: do not use"     },
    { "M_SIG",  M_SIG,      "generate process signal"   },
    { "M_DELAY",    M_DELAY,    "real-time xmit delay"      },
    { "M_CTL",  M_CTL,      "device-specific control message" },
    { "M_IOCTL",    M_IOCTL,    "ioctl; set/get params"     },
    { "M_SETOPTS",  M_SETOPTS,  "set stream head options"   },
    { "M_RSE",  M_RSE,      "reserved for RSE use only" },
    { "M_IOCACK",   M_IOCACK,   "acknowledge ioctl"     },
    { "M_IOCNAK",   M_IOCNAK,   "negative ioctl acknowledge"    },
    { "M_PCPROTO",  M_PCPROTO,  "priority proto message"    },
    { "M_PCSIG",    M_PCSIG,    "generate process signal"   },
    { "M_READ", M_READ,     "generate read notification"    },
    { "M_FLUSH",    M_FLUSH,    "flush your queues"     },
    { "M_STOP", M_STOP,     "stop transmission immediately" },
    { "M_START",    M_START,    "restart transmission after stop" },
    { "M_HANGUP",   M_HANGUP,   "line disconnect"       },
    { "M_ERROR",    M_ERROR,    "send error to stream head" },
    { "M_COPYIN",   M_COPYIN,   "request to copyin data"    },
    { "M_COPYOUT",  M_COPYOUT,  "request to copyout data"   },
    { "M_IOCDATA",  M_IOCDATA,  "response to M_COPYIN and M_COPYOUT" },
    { "M_PCRSE",    M_PCRSE,    "reserved for RSE use only" },
    { "M_STOPI",    M_STOPI,    "stop reception immediately"    },
    { "M_STARTI",   M_STARTI,   "restart reception after stop"  },
    { "M_PCEVENT",  M_PCEVENT,  "Obsoleted: do not use"     },
    { "M_UNHANGUP", M_UNHANGUP, "line reconnect"        },
    { NULL,     0,      NULL                }
};

/* Allocation flow trace events, starting from 0 */
static const char *ftev_alloc[] = {
/* 0 */ ":allocb",
/* 1 */ ":esballoc",
/* 2 */ ":desballoc",
/* 3 */ ":esballoca",
/* 4 */ ":desballoca",
/* 5 */ ":allocbig",
/* 6 */ ":allocbw",
/* 7 */ ":bcallocb",
/* 8 */ ":freeb",
/* 9 */ ":dupb",
/* A */ ":copyb",
};

#define FTEV_PROC_START FTEV_PUT

/* Procedures recorded by flow tracing, starting from 0x100 */
static const char *ftev_proc[] = {
/* 100 */   ":put",
/* 101 */   ":undefined (0x101)",
/* 102 */   ":undefined (0x102)",
/* 103 */   ":undefined (0x103)",
/* 104 */   ":undefined (0x104)",
/* 105 */   ":putq",
/* 106 */   ":getq",
/* 107 */   ":rmvq",
/* 108 */   ":insq",
/* 109 */   ":putbq",
/* 10A */   ":flushq",
/* 10B */   ":undefined (0x10b)",
/* 10C */   ":undefined (0x10c)",
/* 10D */   ":putnext",
/* 10E */   ":rwnext",
};

static const char *db_control_types[] = {
/* 00 */    "data",
/* 01 */    "proto",
/* 02 */    "multidata",
/* 03 */    "unused (0x03)",
/* 04 */    "unused (0x04)",
/* 05 */    "unused (0x05)",
/* 06 */    "unused (0x06)",
/* 07 */    "unused (0x07)",
/* 08 */    "break",
/* 09 */    "passfp",
/* 0a */    "event",
/* 0b */    "sig",
/* 0c */    "delay",
/* 0d */    "ctl",
/* 0e */    "ioctl",
/* 0f */    "unused",
/* 10 */    "setopts",
/* 11 */    "rse",
};

static const char *db_control_hipri_types[] = {
/* 81 */    "iocack",
/* 82 */    "iocnak",
/* 83 */    "pcproto",
/* 84 */    "pcsig",
/* 85 */    "read",
/* 86 */    "flush",
/* 87 */    "stop",
/* 88 */    "start",
/* 89 */    "hangup",
/* 8a */    "error",
/* 8b */    "copyin",
/* 8c */    "copyout",
/* 8d */    "iocdata",
/* 8e */    "pcrse",
/* 8f */    "stopi",
/* 90 */    "starti",
/* 91 */    "pcevent",
/* 92 */    "unhangup",
};


#define A_SIZE(a) (sizeof (a) / sizeof (a[0]))

static void ft_printevent(ushort_t);

static int
streams_parse_flag(const strflags_t ftable[], const char *arg, uint32_t *flag)
{
    int i;

    for (i = 0; ftable[i].strf_name != NULL; i++) {
        if (strcasecmp(arg, ftable[i].strf_name) == 0) {
            *flag |= (1 << i);
            return (0);
        }
    }

    return (-1);
}

static void
streams_flag_usage(const strflags_t ftable[])
{
    int i;

    for (i = 0; ftable[i].strf_name != NULL; i++)
        mdb_printf("%-14s %s\n",
            ftable[i].strf_name, ftable[i].strf_descr);
}

static int
streams_parse_type(const strtypes_t ftable[], const char *arg, uint32_t *flag)
{
    int i;

    for (i = 0; ftable[i].strt_name != NULL; i++) {
        if (strcasecmp(arg, ftable[i].strt_name) == 0) {
            *flag = ftable[i].strt_value;
            return (0);
        }
    }

    return (-1);
}

static void
streams_type_usage(const strtypes_t ftable[])
{
    int i;

    for (i = 0; ftable[i].strt_name != NULL; i++)
        mdb_printf("%-12s %s\n",
            ftable[i].strt_name, ftable[i].strt_descr);
}

int
queue(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    const int QUEUE_FLGDELT = (int)(sizeof (uintptr_t) * 2 + 15);

    char name[MODMAXNAMELEN];
    int nblks = 0;
    uintptr_t maddr;
    mblk_t mblk;
    queue_t q;

    const char *mod = NULL, *flag = NULL, *not_flag = NULL;
    uint_t quiet = FALSE;
    uint_t verbose = FALSE;
    uint32_t mask = 0, not_mask = 0;
    uintptr_t syncq = 0;

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk_dcmd("genunix`queue_cache", "genunix`queue",
            argc, argv) == -1) {
            mdb_warn("failed to walk queue cache");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    if (flags & DCMD_PIPE_OUT)
        quiet = TRUE;

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, TRUE, &verbose,
        'q', MDB_OPT_SETBITS, TRUE, &quiet,
        'm', MDB_OPT_STR, &mod,
        'f', MDB_OPT_STR, &flag,
        'F', MDB_OPT_STR, &not_flag,
        's', MDB_OPT_UINTPTR, &syncq,
        NULL) != argc)
        return (DCMD_USAGE);

    /*
     * If any of the filtering flags is specified, don't print anything
     * except the matching pointer.
     */
    if (flag != NULL || not_flag != NULL || mod != NULL || syncq != NULL)
        quiet = TRUE;

    if (DCMD_HDRSPEC(flags) && !quiet) {
        mdb_printf("%?s %-13s %6s %4s\n",
            "ADDR", "MODULE", "FLAGS", "NBLK");
    }

    if (flag != NULL && streams_parse_flag(qf, flag, &mask) == -1) {
        mdb_warn("unrecognized queue flag '%s'\n", flag);
        streams_flag_usage(qf);
        return (DCMD_USAGE);
    }

    if (not_flag != NULL &&
        streams_parse_flag(qf, not_flag, &not_mask) == -1) {
        mdb_warn("unrecognized queue flag '%s'\n", flag);
        streams_flag_usage(qf);
        return (DCMD_USAGE);
    }

    if (mdb_vread(&q, sizeof (q), addr) == -1) {
        mdb_warn("couldn't read queue at %p", addr);
        return (DCMD_ERR);
    }

    for (maddr = (uintptr_t)q.q_first; maddr != NULL; nblks++) {
        if (mdb_vread(&mblk, sizeof (mblk), maddr) == -1) {
            mdb_warn("couldn't read mblk %p for queue %p",
                maddr, addr);
            break;
        }
        maddr = (uintptr_t)mblk.b_next;
    }

    (void) mdb_qname(&q, name, sizeof (name));

    /*
     * If queue doesn't pass filtering criteria, don't print anything and
     * just return.
     */

    if (mod != NULL && strcmp(mod, name) != 0)
        return (DCMD_OK);

    if (mask != 0 && !(q.q_flag & mask))
        return (DCMD_OK);

    if (not_mask != 0 && (q.q_flag & not_mask))
        return (DCMD_OK);

    if (syncq != 0 && q.q_syncq != (syncq_t *)syncq)
        return (DCMD_OK);

    /*
     * Options are specified for filtering, so If any option is specified on
     * the command line, just print address and exit.
     */
    if (quiet) {
        mdb_printf("%0?p\n", addr);
        return (DCMD_OK);
    }

    mdb_printf("%0?p %-13s %06x %4d %0?p\n",
        addr, name, q.q_flag, nblks, q.q_first);

    if (verbose) {
        int i, arm = 0;

        for (i = 0; qf[i].strf_name != NULL; i++) {
            if (!(q.q_flag & (1 << i)))
                continue;
            if (!arm) {
                mdb_printf("%*s|\n%*s+-->  ",
                    QUEUE_FLGDELT, "", QUEUE_FLGDELT, "");
                arm = 1;
            } else
                mdb_printf("%*s      ", QUEUE_FLGDELT, "");

            mdb_printf("%-12s %s\n",
                qf[i].strf_name, qf[i].strf_descr);
        }
    }

    return (DCMD_OK);
}

int
syncq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    const int SYNC_FLGDELT = (int)(sizeof (uintptr_t) * 2 + 1);
    const int SYNC_TYPDELT = (int)(sizeof (uintptr_t) * 2 + 5);
    syncq_t sq;

    const char *flag = NULL, *not_flag = NULL;
    const char *typ = NULL, *not_typ = NULL;
    uint_t verbose = FALSE;
    uint_t quiet = FALSE;
    uint32_t mask = 0, not_mask = 0;
    uint32_t tmask = 0, not_tmask = 0;
    uint8_t sqtype = 0;

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk_dcmd("genunix`syncq_cache", "genunix`syncq",
            argc, argv) == -1) {
            mdb_warn("failed to walk syncq cache");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    if (flags & DCMD_PIPE_OUT)
        quiet = TRUE;

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, TRUE, &verbose,
        'q', MDB_OPT_SETBITS, TRUE, &quiet,
        'f', MDB_OPT_STR, &flag,
        'F', MDB_OPT_STR, &not_flag,
        't', MDB_OPT_STR, &typ,
        'T', MDB_OPT_STR, &not_typ,
        NULL) != argc)
        return (DCMD_USAGE);

    /*
     * If any of the filtering flags is specified, don't print anything
     * except the matching pointer.
     */
    if (flag != NULL || not_flag != NULL || typ != NULL || not_typ != NULL)
        quiet = TRUE;

    if (DCMD_HDRSPEC(flags) && !quiet) {
        mdb_printf("%?s %s %s %s %s %?s %s %s\n",
            "ADDR", "FLG", "TYP", "CNT", "NQS", "OUTER", "SF", "PRI");
    }

    if (flag != NULL && streams_parse_flag(sqf, flag, &mask) == -1) {
        mdb_warn("unrecognized syncq flag '%s'\n", flag);
        streams_flag_usage(sqf);
        return (DCMD_USAGE);
    }

    if (typ != NULL && streams_parse_flag(sqt, typ, &tmask) == -1) {
        mdb_warn("unrecognized syncq type '%s'\n", typ);
        streams_flag_usage(sqt);
        return (DCMD_USAGE);
    }

    if (not_flag != NULL && streams_parse_flag(sqf, not_flag, &not_mask)
        == -1) {
        mdb_warn("unrecognized syncq flag '%s'\n", not_flag);
        streams_flag_usage(sqf);
        return (DCMD_USAGE);
    }

    if (not_typ != NULL && streams_parse_flag(sqt, not_typ, &not_tmask)
        == -1) {
        mdb_warn("unrecognized syncq type '%s'\n", not_typ);
        streams_flag_usage(sqt);
        return (DCMD_USAGE);
    }

    if (mdb_vread(&sq, sizeof (sq), addr) == -1) {
        mdb_warn("couldn't read syncq at %p", addr);
        return (DCMD_ERR);
    }

    if (mask != 0 && !(sq.sq_flags & mask))
        return (DCMD_OK);

    if (not_mask != 0 && (sq.sq_flags & not_mask))
        return (DCMD_OK);

    sqtype = (sq.sq_type >> 8) & 0xff;

    if (tmask != 0 && !(sqtype & tmask))
        return (DCMD_OK);

    if (not_tmask != 0 && (sqtype & not_tmask))
        return (DCMD_OK);

    /*
     * Options are specified for filtering, so If any option is specified on
     * the command line, just print address and exit.
     */
    if (quiet) {
        mdb_printf("%0?p\n", addr);
        return (DCMD_OK);
    }

    mdb_printf("%0?p %02x  %02x  %-3u %-3u %0?p  %1x %-3d\n",
        addr, sq.sq_flags & 0xff, sqtype, sq.sq_count,
        sq.sq_nqueues, sq.sq_outer, sq.sq_svcflags, sq.sq_pri);

    if (verbose) {
        int i, arm = 0;

        for (i = 0; sqf[i].strf_name != NULL; i++) {
            if (!(sq.sq_flags & (1 << i)))
                continue;
            if (!arm) {
                mdb_printf("%*s|\n%*s+-->  ",
                    SYNC_FLGDELT, "", SYNC_FLGDELT, "");
                arm = 1;
            } else
                mdb_printf("%*s      ", SYNC_FLGDELT, "");

            mdb_printf("%-12s %s\n",
                sqf[i].strf_name, sqf[i].strf_descr);
        }

        for (i = 0; sqt[i].strf_name != NULL; i++) {
            if (!(sqtype & (1 << i)))
                continue;
            if (!arm) {
                mdb_printf("%*s|\n%*s+-->  ",
                    SYNC_TYPDELT, "", SYNC_TYPDELT, "");
                arm = 1;
            } else
                mdb_printf("%*s      ", SYNC_TYPDELT, "");

            mdb_printf("%-12s %s\n",
                sqt[i].strf_name, sqt[i].strf_descr);
        }
    }

    return (DCMD_OK);
}

int
stdata(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    const int STREAM_FLGDELT = (int)(sizeof (uintptr_t) * 2 + 10);

    stdata_t  sd;

    const char *flag = NULL, *not_flag = NULL;
    uint_t verbose = FALSE;
    uint_t quiet = FALSE;
    uint32_t mask = 0, not_mask = 0;

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk_dcmd("genunix`stream_head_cache",
            "genunix`stdata", argc, argv) == -1) {
            mdb_warn("failed to walk stream head cache");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    if (flags & DCMD_PIPE_OUT)
        quiet = TRUE;

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, TRUE, &verbose,
        'q', MDB_OPT_SETBITS, TRUE, &quiet,
        'f', MDB_OPT_STR, &flag,
        'F', MDB_OPT_STR, &not_flag,
        NULL) != argc)
        return (DCMD_USAGE);

    /*
     * If any of the filtering flags is specified, don't print anything
     * except the matching pointer.
     */
    if (flag != NULL || not_flag != NULL)
        quiet = TRUE;

    if (DCMD_HDRSPEC(flags) && !quiet) {
        mdb_printf("%?s %?s %8s %?s %s %s\n",
            "ADDR", "WRQ", "FLAGS", "VNODE", "N/A", "REF");
    }

    if (flag != NULL && streams_parse_flag(stdf, flag, &mask) == -1) {
        mdb_warn("unrecognized stream flag '%s'\n", flag);
        streams_flag_usage(stdf);
        return (DCMD_USAGE);
    }

    if (not_flag != NULL &&
        streams_parse_flag(stdf, not_flag, &not_mask) == -1) {
        mdb_warn("unrecognized stream flag '%s'\n", flag);
        streams_flag_usage(stdf);
        return (DCMD_USAGE);
    }

    if (mdb_vread(&sd, sizeof (sd), addr) == -1) {
        mdb_warn("couldn't read stdata at %p", addr);
        return (DCMD_ERR);
    }

    /*
     * If stream doesn't pass filtering criteria, don't print anything and
     * just return.
     */

    if (mask != 0 && !(sd.sd_flag & mask))
        return (DCMD_OK);

    if (not_mask != 0 && (sd.sd_flag & not_mask))
        return (DCMD_OK);

    /*
     * Options are specified for filtering, so If any option is specified on
     * the command line, just print address and exit.
     */
    if (quiet) {
        mdb_printf("%0?p\n", addr);
        return (DCMD_OK);
    }

    mdb_printf("%0?p %0?p %08x %0?p %d/%d %d\n",
        addr, sd.sd_wrq, sd.sd_flag, sd.sd_vnode,
        sd.sd_pushcnt, sd.sd_anchor, sd.sd_refcnt);

    if (verbose) {
        int i, arm = 0;

        for (i = 0; stdf[i].strf_name != NULL; i++) {
            if (!(sd.sd_flag & (1 << i)))
                continue;
            if (!arm) {
                mdb_printf("%*s|\n%*s+-->  ",
                    STREAM_FLGDELT, "", STREAM_FLGDELT, "");
                arm = 1;
            } else
                mdb_printf("%*s      ", STREAM_FLGDELT, "");

            mdb_printf("%-12s %s\n",
                stdf[i].strf_name, stdf[i].strf_descr);
        }
    }

    return (DCMD_OK);
}

/*ARGSUSED*/
static void
qprint_syncq(queue_t *addr, queue_t *q)
{
    mdb_printf("%p\n", q->q_syncq);
}

/*ARGSUSED*/
static void
qprint_stream(queue_t *addr, queue_t *q)
{
    mdb_printf("%p\n", q->q_stream);
}

static void
qprint_wrq(queue_t *addr, queue_t *q)
{
    mdb_printf("%p\n", ((q)->q_flag & QREADR? (addr)+1: (addr)));
}

static void
qprint_rdq(queue_t *addr, queue_t *q)
{
    mdb_printf("%p\n", ((q)->q_flag & QREADR? (addr): (addr)-1));
}

static void
qprint_otherq(queue_t *addr, queue_t *q)
{
    mdb_printf("%p\n", ((q)->q_flag & QREADR? (addr)+1: (addr)-1));
}

static int
q2x(uintptr_t addr, int argc, qprint_func prfunc)
{
    queue_t q;

    if (argc != 0)
        return (DCMD_USAGE);

    if (mdb_vread(&q, sizeof (q), addr) == -1) {
        mdb_warn("couldn't read queue at %p", addr);
        return (DCMD_ERR);
    }

    prfunc((queue_t *)addr, &q);

    return (DCMD_OK);
}


/*ARGSUSED*/
int
q2syncq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (q2x(addr, argc, qprint_syncq));
}

/*ARGSUSED*/
int
q2stream(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (q2x(addr, argc, qprint_stream));
}

/*ARGSUSED*/
int
q2rdq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (q2x(addr, argc, qprint_rdq));
}

/*ARGSUSED*/
int
q2wrq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (q2x(addr, argc, qprint_wrq));
}

/*ARGSUSED*/
int
q2otherq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (q2x(addr, argc, qprint_otherq));
}

static int
sd2x(uintptr_t addr, int argc, sdprint_func prfunc)
{
    stdata_t sd;

    if (argc != 0)
        return (DCMD_USAGE);

    if (mdb_vread(&sd, sizeof (sd), addr) == -1) {
        mdb_warn("couldn't read stream head at %p", addr);
        return (DCMD_ERR);
    }

    prfunc((stdata_t *)addr, &sd);

    return (DCMD_OK);
}

/*ARGSUSED*/
static void
sdprint_wrq(stdata_t *addr, stdata_t *sd)
{
    mdb_printf("%p\n", sd->sd_wrq);
}

static void
sdprint_mate(stdata_t *addr, stdata_t *sd)
{
    mdb_printf("%p\n", sd->sd_mate ? sd->sd_mate : addr);
}

/*ARGSUSED*/
int
str2mate(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (sd2x(addr, argc, sdprint_mate));
}

/*ARGSUSED*/
int
str2wrq(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    return (sd2x(addr, argc, sdprint_wrq));
}


/*
 * If this syncq is a part of the queue pair structure, find the queue for it.
 */
/*ARGSUSED*/
int
syncq2q(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    syncq_t sq;
    queue_t q;
    queue_t *qp;

    if (argc != 0)
        return (DCMD_USAGE);

    if (mdb_vread(&sq, sizeof (sq), addr) == -1) {
        mdb_warn("couldn't read syncq at %p", addr);
        return (DCMD_ERR);
    }

    /* Try to find its queue */
    qp = (queue_t *)addr - 2;

    if ((mdb_vread(&q, sizeof (q), (uintptr_t)qp) == -1) ||
        (q.q_syncq != (syncq_t *)addr)) {
        mdb_warn("syncq2q: %p is not part of any queue\n", addr);
        return (DCMD_ERR);
    } else
        mdb_printf("%p\n", qp);

    return (DCMD_OK);
}


int
queue_walk_init(mdb_walk_state_t *wsp)
{
    if (wsp->walk_addr == NULL &&
        mdb_readvar(&wsp->walk_addr, "qhead") == -1) {
        mdb_warn("failed to read 'qhead'");
        return (WALK_ERR);
    }

    wsp->walk_data = mdb_alloc(sizeof (queue_t), UM_SLEEP);
    return (WALK_NEXT);
}

int
queue_link_step(mdb_walk_state_t *wsp)
{
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (queue_t), wsp->walk_addr) == -1) {
        mdb_warn("failed to read queue at %p", wsp->walk_addr);
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr, wsp->walk_data,
        wsp->walk_cbdata);

    wsp->walk_addr = (uintptr_t)(((queue_t *)wsp->walk_data)->q_link);
    return (status);
}

int
queue_next_step(mdb_walk_state_t *wsp)
{
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (queue_t), wsp->walk_addr) == -1) {
        mdb_warn("failed to read queue at %p", wsp->walk_addr);
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr, wsp->walk_data,
        wsp->walk_cbdata);

    wsp->walk_addr = (uintptr_t)(((queue_t *)wsp->walk_data)->q_next);
    return (status);
}

void
queue_walk_fini(mdb_walk_state_t *wsp)
{
    mdb_free(wsp->walk_data, sizeof (queue_t));
}

int
str_walk_init(mdb_walk_state_t *wsp)
{
    stdata_t s;

    if (wsp->walk_addr == NULL) {
        mdb_warn("walk must begin at address of stdata_t\n");
        return (WALK_ERR);
    }

    if (mdb_vread(&s, sizeof (s), wsp->walk_addr) == -1) {
        mdb_warn("failed to read stdata at %p", wsp->walk_addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)s.sd_wrq;
    wsp->walk_data = mdb_alloc(sizeof (queue_t) * 2, UM_SLEEP);

    return (WALK_NEXT);
}

int
strr_walk_step(mdb_walk_state_t *wsp)
{
    queue_t *rq = wsp->walk_data, *wq = rq + 1;
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (queue_t) * 2,
        wsp->walk_addr - sizeof (queue_t)) == -1) {
        mdb_warn("failed to read queue pair at %p",
            wsp->walk_addr - sizeof (queue_t));
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr - sizeof (queue_t),
        rq, wsp->walk_cbdata);

    if (wq->q_next != NULL)
        wsp->walk_addr = (uintptr_t)wq->q_next;
    else
        wsp->walk_addr = mdb_qwnext(wq);

    return (status);
}

int
strw_walk_step(mdb_walk_state_t *wsp)
{
    queue_t *rq = wsp->walk_data, *wq = rq + 1;
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (queue_t) * 2,
        wsp->walk_addr - sizeof (queue_t)) == -1) {
        mdb_warn("failed to read queue pair at %p",
            wsp->walk_addr - sizeof (queue_t));
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr, wq, wsp->walk_cbdata);

    if (wq->q_next != NULL)
        wsp->walk_addr = (uintptr_t)wq->q_next;
    else
        wsp->walk_addr = mdb_qwnext(wq);

    return (status);
}

void
str_walk_fini(mdb_walk_state_t *wsp)
{
    mdb_free(wsp->walk_data, sizeof (queue_t) * 2);
}

static int
print_qpair(uintptr_t addr, const queue_t *q, uint_t *depth)
{
    static const char box_lid[] =
        "+-----------------------+-----------------------+\n";
    static const char box_sep[] =
        "|                       |                       |\n";

    char wname[32], rname[32], info1[256], *info2;

    if (*depth != 0) {
        mdb_printf("            |                       ^\n");
        mdb_printf("            v                       |\n");
    } else
        mdb_printf("\n");

    (void) mdb_qname(_WR(q), wname, sizeof (wname));
    (void) mdb_qname(_RD(q), rname, sizeof (rname));

    mdb_qinfo(_WR(q), info1, sizeof (info1));
    if ((info2 = strchr(info1, '\n')) != NULL)
        *info2++ = '\0';
    else
        info2 = "";

    mdb_printf(box_lid);
    mdb_printf("| 0x%-19p | 0x%-19p | %s\n",
        addr, addr - sizeof (queue_t), info1);

    mdb_printf("| %<b>%-21s%</b> | %<b>%-21s%</b> |", wname, rname);
    mdb_flush(); /* Account for buffered terminal sequences */

    mdb_printf(" %s\n", info2);
    mdb_printf(box_sep);

    mdb_qinfo(_RD(q), info1, sizeof (info1));
    if ((info2 = strchr(info1, '\n')) != NULL)
        *info2++ = '\0';
    else
        info2 = "";

    mdb_printf("| cnt = 0t%-13lu | cnt = 0t%-13lu | %s\n",
        _WR(q)->q_count, _RD(q)->q_count, info1);

    mdb_printf("| flg = 0x%08x      | flg = 0x%08x      | %s\n",
        _WR(q)->q_flag, _RD(q)->q_flag, info2);

    mdb_printf(box_lid);
    *depth += 1;
    return (0);
}

/*ARGSUSED*/
int
stream(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    uint_t d = 0;   /* Depth counter for print_qpair */

    if (argc != 0 || !(flags & DCMD_ADDRSPEC))
        return (DCMD_USAGE);

    if (mdb_pwalk("writeq", (mdb_walk_cb_t)print_qpair, &d, addr) == -1) {
        mdb_warn("failed to walk writeq");
        return (DCMD_ERR);
    }

    return (DCMD_OK);
}

int
mblk_walk_init(mdb_walk_state_t *wsp)
{
    wsp->walk_data = mdb_alloc(sizeof (mblk_t), UM_SLEEP);
    return (WALK_NEXT);
}

int
b_cont_step(mdb_walk_state_t *wsp)
{
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (mblk_t), wsp->walk_addr) == -1) {
        mdb_warn("failed to read mblk at %p", wsp->walk_addr);
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr, wsp->walk_data,
        wsp->walk_cbdata);

    wsp->walk_addr = (uintptr_t)(((mblk_t *)wsp->walk_data)->b_cont);
    return (status);
}

int
b_next_step(mdb_walk_state_t *wsp)
{
    int status;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(wsp->walk_data, sizeof (mblk_t), wsp->walk_addr) == -1) {
        mdb_warn("failed to read mblk at %p", wsp->walk_addr);
        return (WALK_DONE);
    }

    status = wsp->walk_callback(wsp->walk_addr, wsp->walk_data,
        wsp->walk_cbdata);

    wsp->walk_addr = (uintptr_t)(((mblk_t *)wsp->walk_data)->b_next);
    return (status);
}

void
mblk_walk_fini(mdb_walk_state_t *wsp)
{
    mdb_free(wsp->walk_data, sizeof (mblk_t));
}

/* ARGSUSED */
int
mblk2dblk(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mblk_t mb;

    if (argc != 0)
        return (DCMD_USAGE);

    if (mdb_vread(&mb, sizeof (mb), addr) == -1) {
        mdb_warn("couldn't read mblk at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("%p\n", mb.b_datap);
    return (DCMD_OK);
}


static void
mblk_error(int *error, uintptr_t addr, char *message)
{
    if (!*error)
        mdb_printf("%?lx: ", addr);
    else
        mdb_printf(", ");
    mdb_printf("%s", message);
    *error = 1;
}

int
mblk_verify(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mblk_t  mb;
    dblk_t  db;
    int error = 0;

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk_dcmd("streams_mblk", "mblk_verify", argc, argv) ==
            -1) {
            mdb_warn("can't walk mblk cache");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    if (mdb_vread(&mb, sizeof (mblk_t), addr) == -1) {
        mdb_warn("can't read mblk_t at 0x%lx", addr);
        return (DCMD_ERR);
    }

    if (mdb_vread(&db, sizeof (dblk_t), (uintptr_t)mb.b_datap) == -1) {
        mdb_warn("%?lx: invalid b_datap pointer\n", addr);
        return (DCMD_ERR);
    }

    if (mb.b_rptr < db.db_base || mb.b_rptr > db.db_lim)
        mblk_error(&error, addr, "b_rptr out of range");

    if (mb.b_wptr < db.db_base || mb.b_wptr > db.db_lim)
        mblk_error(&error, addr, "b_wptr out of range");

    if (error)
        mdb_printf("\n");

    return (error ? DCMD_ERR : DCMD_OK);
}

int
mblk_prt(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    const int MBLK_FLGDELT = (int)(sizeof (uintptr_t) * 2 + 15);
    mblk_t mblk;
    dblk_t dblk;
    int b_flag;
    int db_type;
    int mblklen;
    uint64_t len = ~0UL;
    uint64_t glen = ~0UL;
    uint64_t llen = ~0UL;
    uint64_t blen = ~0UL;
    const char *dbtype;
    const char *flag = NULL, *not_flag = NULL;
    const char *typ = NULL, *not_typ = NULL;
    uintptr_t  dbaddr = 0;
    uint32_t tmask = 0, not_tmask = 0;
    uint32_t mask = 0, not_mask = 0;
    uint_t quiet = FALSE;
    uint_t verbose = FALSE;

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk_dcmd("genunix`streams_mblk", "genunix`mblk",
            argc, argv) == -1) {
            mdb_warn("failed to walk mblk cache");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    if (flags & DCMD_PIPE_OUT)
        quiet = TRUE;

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, TRUE, &verbose,
        'q', MDB_OPT_SETBITS, TRUE, &quiet,
        'f', MDB_OPT_STR, &flag,
        'F', MDB_OPT_STR, &not_flag,
        't', MDB_OPT_STR, &typ,
        'T', MDB_OPT_STR, &not_typ,
        'l', MDB_OPT_UINT64, &len,
        'L', MDB_OPT_UINT64, &llen,
        'G', MDB_OPT_UINT64, &glen,
        'b', MDB_OPT_UINT64, &blen,
        'd', MDB_OPT_UINTPTR, &dbaddr,
        NULL) != argc)
        return (DCMD_USAGE);

    /*
     * If any of the filtering flags is specified, don't print anything
     * except the matching pointer.
     */
    if ((flag != NULL) || (not_flag != NULL) || (typ != NULL) ||
        (not_typ != NULL) || (len != ~0UL) || (glen != ~0UL) ||
        (llen != ~0UL) || (blen != ~0UL) || (dbaddr != 0))
        quiet = TRUE;

    if (flag != NULL && streams_parse_flag(mbf, flag, &mask) == -1) {
        mdb_warn("unrecognized mblk flag '%s'\n", flag);
        streams_flag_usage(mbf);
        return (DCMD_USAGE);
    }

    if (not_flag != NULL &&
        streams_parse_flag(mbf, not_flag, &not_mask) == -1) {
        mdb_warn("unrecognized mblk flag '%s'\n", flag);
        streams_flag_usage(mbf);
        return (DCMD_USAGE);
    }

    if (typ != NULL && streams_parse_type(mbt, typ, &tmask) == -1) {
        mdb_warn("unrecognized dblk type '%s'\n", typ);
        streams_type_usage(mbt);
        return (DCMD_USAGE);
    }

    if (not_typ != NULL && streams_parse_type(mbt, not_typ, &not_tmask)
        == -1) {
        mdb_warn("unrecognized dblk type '%s'\n", not_typ);
        streams_type_usage(mbt);
        return (DCMD_USAGE);
    }

    if (DCMD_HDRSPEC(flags) && !quiet) {
        mdb_printf("%?s %2s %-7s %-5s %-5s %?s %?s\n",
            "ADDR", "FL", "TYPE", "LEN", "BLEN", "RPTR", "DBLK");
    }

    if (mdb_vread(&mblk, sizeof (mblk), addr) == -1) {
        mdb_warn("couldn't read mblk at %p", addr);
        return (DCMD_ERR);
    }
    b_flag = mblk.b_flag;

    if (mask != 0 && !(b_flag & mask))
        return (DCMD_OK);

    if (not_mask != 0 && (b_flag & not_mask))
        return (DCMD_OK);

    if (mdb_vread(&dblk, sizeof (dblk), (uintptr_t)(mblk.b_datap)) == -1) {
        mdb_warn("couldn't read dblk at %p/%p", addr, mblk.b_datap);
        return (DCMD_ERR);
    }
    db_type = dblk.db_type;

    /* M_DATA is 0, so tmask has special value 0xff for it */
    if ((tmask != 0) &&
        (((tmask == M_DATA_T) && (db_type != M_DATA)) ||
        ((tmask != M_DATA_T) && (db_type != tmask))))
        return (DCMD_OK);


    if ((not_tmask != 0) &&
        (((not_tmask == M_DATA_T) && (db_type == M_DATA)) ||
        (db_type == not_tmask)))
        return (DCMD_OK);

    if (dbaddr != 0 && (uintptr_t)mblk.b_datap != dbaddr)
        return (DCMD_OK);

    mblklen = MBLKL(&mblk);

    if ((len != ~0UL) && (len != mblklen))
        return (DCMD_OK);

    if ((llen != ~0Ul) && (mblklen > (int)llen))
        return (DCMD_OK);

    if ((glen != ~0Ul) && (mblklen < (int)glen))
        return (DCMD_OK);

    if ((blen != ~0UL) && (blen != (dblk.db_lim - dblk.db_base)))
        return (DCMD_OK);

    /*
     * Options are specified for filtering, so If any option is specified on
     * the command line, just print address and exit.
     */
    if (quiet) {
        mdb_printf("%0?p\n", addr);
        return (DCMD_OK);
    }

    /* Figure out symbolic DB_TYPE */
    if (db_type < A_SIZE(db_control_types)) {
        dbtype = db_control_types[db_type];
    } else {
        /*
         * Must be a high-priority message -- adjust so that
         * "QPCTL + 1" corresponds to db_control_hipri_types[0]
         */
        db_type -= (QPCTL + 1);
        if (db_type >= 0 && db_type < A_SIZE(db_control_hipri_types))
            dbtype = db_control_hipri_types[db_type];
        else
            dbtype = "UNKNOWN";
    }

    mdb_printf("%0?p %-2x %-7s %-5d %-5d %0?p %0?p\n",
        addr, b_flag, dbtype, mblklen, dblk.db_lim - dblk.db_base,
        mblk.b_rptr, mblk.b_datap);

    if (verbose) {
        int i, arm = 0;

        for (i = 0; mbf[i].strf_name != NULL; i++) {
            if (!(b_flag & (1 << i)))
                continue;
            if (!arm) {
                mdb_printf("%*s|\n%*s+-->  ",
                    MBLK_FLGDELT, "", MBLK_FLGDELT, "");
                arm = 1;
            } else
                mdb_printf("%*s      ", MBLK_FLGDELT, "");

            mdb_printf("%-12s %s\n",
                mbf[i].strf_name, mbf[i].strf_descr);
        }
    }
    return (DCMD_OK);
}

/*
 * Streams flow trace walkers.
 */

int
strftblk_walk_init(mdb_walk_state_t *wsp)
{
    ftblkdata_t *ftd;
    dblk_t  db;

    /* Get the dblock from the address */
    if (mdb_vread(&db, sizeof (dblk_t), wsp->walk_addr) == -1) {
        mdb_warn("failed to read dblk at %p", wsp->walk_addr);
        return (WALK_ERR);
    }

    /* Is there any flow trace data? */
    if (db.db_fthdr == NULL) {
        return (WALK_DONE);
    }

    wsp->walk_addr = (uintptr_t)((char *)db.db_fthdr +
        offsetof(fthdr_t, first));

    ftd = mdb_alloc(sizeof (ftblkdata_t), UM_SLEEP);
    ftd->ft_ix = 0;
    ftd->ft_in_evlist = B_FALSE;
    wsp->walk_data = ftd;

    return (WALK_NEXT);
}

int
strftblk_step(mdb_walk_state_t *wsp)
{
    ftblkdata_t *ftd;
    ftblk_t *ftbp;
    int status = WALK_NEXT;

    if (wsp->walk_addr == NULL)
        return (WALK_DONE);

    ftd = (ftblkdata_t *)wsp->walk_data;
    ftbp = &(ftd->ft_data);

    if (! ftd->ft_in_evlist) {
        /* Read a new ft block */
        if (mdb_vread(ftbp, sizeof (ftblk_t),
            wsp->walk_addr) == -1) {
            mdb_warn("failed to read ftblk at %p", wsp->walk_addr);
            return (WALK_ERR);
        }
        /*
         * Check correctness of the index field.
         */
        if (ftbp->ix < 0 || ftbp->ix > FTBLK_EVNTS) {
            mdb_warn("ftblk: incorrect index value %i\n", ftbp->ix);
            return (WALK_ERR);
        }
        ftd->ft_ix = 1;
        ftd->ft_in_evlist = B_TRUE;
    }

    if (ftd->ft_ix > ftbp->ix) {
        ftd->ft_in_evlist = B_FALSE;
        /* End of event list reached - move to the next event block */
        wsp->walk_addr = (uintptr_t)ftbp->nxt;
    } else {
        /* Print event address */
        status = wsp->walk_callback((uintptr_t)((char *)wsp->walk_addr +
            offsetof(ftblk_t, ev) +
            (ftd->ft_ix - 1) * sizeof (struct ftevnt)),
            wsp->walk_data, wsp->walk_cbdata);
        ftd->ft_ix++;
    }

    return (status);
}


void
strftblk_walk_fini(mdb_walk_state_t *wsp)
{
    mdb_free(wsp->walk_data, sizeof (ftblkdata_t));
}

/*ARGSUSED*/
int
strftevent(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    struct ftevnt ev;
    char modname[MODMAXNAMELEN];

    if (!(flags & DCMD_ADDRSPEC))
        return (DCMD_USAGE);

    if (DCMD_HDRSPEC(flags)) {
        mdb_printf("%?s %?s %s %s %-24s  %s\n",
            "ADDR", "MID", "EVNT", "DATA", "NAME", "EVENT");
    }

    if (mdb_vread(&ev, sizeof (ev), addr) == -1) {
        mdb_warn("couldn't read ft event at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("%0?p %0?p %4x %4x",
        addr, ev.mid, ev.evnt, ev.data);

    if (ev.evnt & FTEV_QMASK) {
        if (mdb_readstr(modname, sizeof (modname),
            (uintptr_t)ev.mid) == -1)
            mdb_warn("couldn't read module name at %p", ev.mid);
        mdb_printf(" %-24s", modname);
    } else
        mdb_printf(" %-24a", ev.mid);

    ft_printevent(ev.evnt);

    mdb_printf("\n");

    return (DCMD_OK);
}

static void
ft_printevent(ushort_t ev)
{
    ushort_t proc_ev = (ev & (FTEV_PROC_START | 0xFF)) - FTEV_PROC_START;
    ushort_t alloc_ev = ev & FTEV_CALLER;

    /* Get event class first */
    if (ev & FTEV_PROC_START) {
        if (proc_ev >= A_SIZE(ftev_proc))
            mdb_printf("  undefined");
        else
            mdb_printf("  %s", ftev_proc[proc_ev]);
    } else if (alloc_ev >= A_SIZE(ftev_alloc))
        mdb_printf("  undefined");
    else
        mdb_printf("  %s", ftev_alloc[alloc_ev]);

    /* Print event modifiers, if any */

    if (ev & FTEV_PS)
        mdb_printf(" | PS");
    if (ev & FTEV_CS)
        mdb_printf(" | CS");
    if (ev & FTEV_ISWR)
        mdb_printf(" | ISWR");
}

/*
 * Help functions for STREAMS debugging facilities.
 */
void
queue_help(void)
{
    mdb_printf("Print queue information for a given queue pointer.\n"
        "\nWithout the address of a \"queue_t\" structure given, print "
        "information about all\n"
        "queues in the \"queue_cache\".\n\n"
        "Options:\n"
        "   -v:\t\tbe verbose - print symbolic flags falues\n"
        "   -q:\t\tbe quiet - print queue pointer only\n"
        "   -f flag:\tprint only queues with flag set\n"
        "   -F flag:\tprint only queues with flag NOT set\n"
        "   -m modname:\tprint only queues with specified module name\n"
        "   -s syncq_addr:\tprint only queues which use specified syncq\n\n"
        "Available conversions:\n"
        "   q2rdq:      given a queue addr print read queue pointer\n"
        "   q2wrq:      given a queue addr print write queue pointer\n"
        "   q2otherq:   given a queue addr print other queue pointer\n"
        "   q2syncq:    given a queue addr print syncq pointer"
        " (::help syncq)\n"
        "   q2stream:   given a queue addr print its stream pointer\n"
        "\t\t(see ::help stream and ::help stdata)\n\n"
        "To walk q_next pointer of the queue use\n"
        "   queue_addr::walk qnext\n");
}

void
syncq_help(void)
{
    mdb_printf("Print syncq information for a given syncq pointer.\n"
        "\nWithout the address of a \"syncq_t\" structure given, print "
        "information about all\n"
        "syncqs in the \"syncq_cache\".\n\n"
        "Options:\n"
        "   -v:\t\tbe verbose - print symbolic flags falues\n"
        "   -q:\t\tbe quiet - print syncq pointer only\n"
        "   -f flag:\tprint only syncqs with flag set\n"
        "   -F flag:\tprint only syncqs with flag NOT set\n"
        "   -t type:\tprint only syncqs with specified type\n"
        "   -T type:\tprint only syncqs with do NOT have specified type\n\n"
        "Available conversions:\n"
        "   syncq2q:\tgiven a syncq addr print queue address of the\n"
        "\t\t\tenclosing queue, if it is part of a queue\n\n"
        "See also: \"::help queue\" and \"::help stdata\"\n");
}

void
stdata_help(void)
{
    mdb_printf("Print stdata information for a given stdata pointer.\n"
        "\nWithout the address of a \"stdata_t\" structure given, print "
        "information about all\n"
        "stream head pointers from the \"stream_head_cache\".\n\n"
        "Fields printed:\n"
        "   ADDR:\tstream head address\n"
        "   WRQ:\twrite queue pointer\n"
        "   FLAGS:\tstream head flags (use -v to show in symbolic form)\n"
        "   VNODE:\tstream vnode pointer\n"
        "   N/A:\tpushcount and anchor positions\n"
        "   REF:\tstream head reference counter\n\n"
        "Options:\n"
        "   -v:\t\tbe verbose - print symbolic flags falues\n"
        "   -q:\t\tbe quiet - print stdata pointer only\n"
        "   -f flag:\tprint only stdatas with flag set\n"
        "   -F flag:\tprint only stdatas with flag NOT set\n\n"
        "Available conversions:\n"
        "   str2mate:\tgiven a stream head addr print its mate\n"
        "   str2wrq:\tgiven a stream head addr print its write queue\n\n"
        "See also: \"::help queue\" and \"::help syncq\"\n");
}

void
mblk_help(void)
{
    mdb_printf("Print mblock information for a given mblk pointer.\n"
        "Without the address, print information about all mblocks.\n\n"
        "Fields printed:\n"
        "   ADDR:\tmblk address\n"
        "   FL:\tFlags\n"
        "   TYPE:\tType of corresponding dblock\n"
        "   LEN:\tData length as b_wptr - b_rptr\n"
        "   BLEN:\tDblock space as db_lim - db_base\n"
        "   RPTR:\tRead pointer\n"
        "   DBLK:\tDblock pointer\n\n"
        "Options:\n"
        "   -v:\t\tbe verbose - print symbolic flags falues\n"
        "   -q:\t\tbe quiet - print mblk pointer only\n"
        "   -d dbaddr:\t\tprint mblks with specified dblk address\n"
        "   -f flag:\tprint only mblks with flag set\n"
        "   -F flag:\tprint only mblks with flag NOT set\n"
        "   -t type:\tprint only mblks of specified db_type\n"
        "   -T type:\tprint only mblks other then the specified db_type\n"
        "   -l len:\t\ttprint only mblks with MBLKL == len\n"
        "   -L len:\t\tprint only mblks with MBLKL <= len \n"
        "   -G len:\t\tprint only mblks with MBLKL >= len \n"
        "   -b len:\t\tprint only mblks with db_lim - db_base == len\n"
        "\n");
}